In 1683 when probate courts were set up, most people in rural areas fell under the godser (feudal or manorial estates). In 1733, a law was put into effect giving feudal lords almost complete control over those working on their estates. Those persons under the estate jurisdiction remained there until shortly after 1788 when the law from 1733 was revoked. At that time the estate workers fell under the administration of the herreder (districts).
Although the law had been revoked in 1788, many of the feudal lords retained their jurisdictional role, sometimes until 1817. There were some entities that continued past that time and retained their right as a gods (estate) jurisdiction even after a law in 1850 put a complete stop to it. These exceptions had been given land to provide for their financial support and were allowed to continue in their administration of probate estates. They were places such as the university in Copenhagen, hospitals, institutions, and cathedrals.
All those in a county who did not fall under the godser (manorial estates) or rytterdistrikter (cavalry districts) were under the amtstue (county administration). This group included the people like manorial lords and farm owners. A decree on 4 September 1793 changed that, though, so their administration was transferred to the herreder (districts).
The rytterdistrikter (cavalry districts) were begun around 1670 when the national cavalry were assigned royal land estates so they would have the financial support they needed. In 1695 there were ten of these districts, and in 1720 that number had increased to twelve. These cavalry districts were discontinued as their lands were sold between 1760 and 1770.
The final jurisdiction that was given charge over probates were the herreder (districts). Records exist on this level beginning about 1793 and continue to 1919 when the responsibility of probate matters was turned over to the underrets dommer (local judge). The number of people and classes who fell under this level of jurisdiction increased as others were discontinued or changed.
There was also a class that still did not completely fit under any of these categories. Those were the clergymen and their assistants, and persons who worked with the schools along with their families. These people had their own district probate courts—the herreds provsti (deanery).
In addition to the district administrations, the rural areas had another subdivision for probate matters called birker. You will want to see if these exist when there are no records under the herreder, as they served the same purpose.
This division of probate jurisdictions can be confusing at times, but when you consider what occupation your ancestor was engaged in and the time period they would have left their probate records, it makes it easier to decide which level you should consult for probate information.